Ansible Role: Docker

Install and configure the Docker container runtime. On Debian the role installs Docker CE from the official Docker apt repository, on Alpine it installs the distribution packages.

Requirements

Operating System	Notes
Debian	Docker CE from download.docker.com (deb822 repository, amd64 or arm64)
Alpine	docker, docker-compose and py3-docker-py from apk

The role has no role dependencies (meta/main.yaml).

Variables

Variable	Required	Default	Description
type	No	""	Object type. Defined in the defaults, but currently not referenced by any task (see below).

The AppArmor removal is not controlled by type: it runs whenever the host reports ansible_facts["virtualization_type"] == "lxc".

Example

type: "server"

What the role does

1. On LXC guests, purge the apparmor package (Debian only) and reboot the guest through the reboot container handler. Handlers are flushed before Docker is installed.
2. Alpine: install docker, docker-compose and py3-docker-py, then start and enable the docker service.
3. Debian:
   • purge the old containerd, docker-compose, docker-doc, docker.io, podman-docker and runc packages;
   • download the Docker GPG key to /etc/apt/keyrings/docker.asc;
   • remove the legacy /etc/apt/sources.list.d/docker.list (marked in the code for removal after 2026-10-20);
   • add the docker deb822 repository (stable component);
   • install containerd.io, docker-ce, docker-ce-cli, docker-compose-plugin, python3-pip, python3-docker and nfs-common.

Usage

Run playbook.yaml through Semaphore. The playbook first runs ansible-galaxy install -f -r roles/requirements.yml on the controller (works around a Semaphore bug) and then includes the docker role on all hosts with become.

The role is also used as a dependency by other playbooks (for example forgejo and grafana).